Two Brothers Up-and-Down

12% grade

2024 date tba
Idaho Springs, CO

10k with ~1,800' of climbing - Big Brother

5k with ~570' of climbing - Baby Brother


A mix of 2wd dirt and paved roads.

Both races start/finish on 23rd, on the W side of the park, by the river. Go N for 2 blocks. Left on Virginia to where it ends. Right up Virginia Canyon, where the real climbing begins. Stay on the E side of the paved road both ways (right, on the way up). The next 1/2mi climbs at ~10%. At the dirt, the courses split.

5k: Take a sharp right and continue up Virginia Canyon (aka Oh My God) rd. Follow the dirt road for another ~3/4mi. The climb is a more moderate ~7%. Turn around, and return the same way.

10k: Stay straight at the start of the dirt, onto Two Brothers Rd. The dirt road is steep, ~12%, but not too rocky. In another mile, it flattens out briefly at a second junction with Virginia Canyon. There will be an aid station here. Continue straight up Two Brothers rd. It gets even steeper after the aid station with sections >15%. The climb mellows the last ~1/4mi. Turn around just before the paved road at the aid station. Return the same way.


Volunteers are needed for registration and pickup, finish line, and aid stations. Volunteers earn a free entry for another race.